2012-02-22 16:02:40

by Stefan Hajnoczi

[permalink] [raw]
Subject: [tip:perf/core] perf tools: Allow expressions in __print_symbolic( ) fields

Commit-ID: a5a178e1ae0192e405830f1bba84548992124e88
Gitweb: http://git.kernel.org/tip/a5a178e1ae0192e405830f1bba84548992124e88
Author: Stefan Hajnoczi <[email protected]>
AuthorDate: Sun, 4 Sep 2011 16:08:59 +0100
Committer: Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Fri, 17 Feb 2012 16:34:08 -0200

perf tools: Allow expressions in __print_symbolic() fields

The __print_symbolic() function takes a sequence of key-value pairs for
pretty-printing a constant. The new kvm:kvm_exit print fmt uses the
expression:

__print_symbolic(..., { 0x040 + 1, "DB excp" }, ...)

Currently only atoms are supported and this print fmt fails to parse.
This patch adds support for expressions instead of just atoms so that
0x040 + 1 is parsed successfully. Also add arg_num_eval() support for
the '+' operator.

Acked-by: Steven Rostedt <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Steven Rostedt <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Stefan Hajnoczi <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/perf/util/trace-event-parse.c | 12 ++++++++++++
1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index e0a4f65..a4088ce 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -1423,6 +1423,11 @@ static long long arg_num_eval(struct print_arg *arg)
die("unknown op '%s'", arg->op.op);
}
break;
+ case '+':
+ left = arg_num_eval(arg->op.left);
+ right = arg_num_eval(arg->op.right);
+ val = left + right;
+ break;
default:
die("unknown op '%s'", arg->op.op);
}
@@ -1483,6 +1488,13 @@ process_fields(struct event *event, struct print_flag_sym **list, char **tok)

free_token(token);
type = process_arg(event, arg, &token);
+
+ if (type == EVENT_OP)
+ type = process_op(event, arg, &token);
+
+ if (type == EVENT_ERROR)
+ goto out_free;
+
if (test_type_token(type, token, EVENT_DELIM, ","))
goto out_free;